FAMILY FORMICARIIDAE 2O9 



for all others. I find, however, that all are the nominate race 

 laemosticta. This is very slightly darker, and in the male the breast 

 and upper abdomen are marked rather heavily with dull black in the 

 form of large somewhat irregular spots. Myrmeciza laemosticta 

 palliata Todd, which we have in series from collections made in 

 Colombia by M. A. Carriker, Jr., is duller brown above, with the 

 crown gray, rather than black, and paler below, both in shade of 

 gray on the breast and abdomen, and in the brown of flanks and 

 under tail coverts. The male lacks the irregular black spots on the 

 breast found in M. I. laemosticta. 



MYRMECIZA IMMACULATA (Lafresnaye) : Immaculate Ant-bird, 

 Hormiguero Imnaculado 



Thamnophilus inimaculatus Lafresnaye, Rev. Zool., September 1845, p. 340. 

 (Bogota, Colombia.) 



Medium size ; male black ; female dark brown with forepart of 

 head black. 



Description. — Length 170-190 mm. Adult male, black; anterior 

 lesser wing coverts, a line around bend of wing, and edging on alula 

 white, the extent of the white on the shoulder variable. 



Adult female, side of head including lores and malar region, black; 

 elsewhere plain dark brown, paler on under surface. 



This is a little-known species found from Costa Rica and Panama 

 to Colombia, south to western Ecuador, and east to western Vene- 

 zuela. Four geographic races currently are recognized, of which two 

 are found in Panama. 



MYRMECIZA IMMACULATA ZELEDONI Ridgway 



Myrmecisa zeledoni Ridgway, Proc. Biol. Soc. Washington, vol. 22, April 17, 

 1909, p. 74. (Guayabo, Costa Rica.) 



Characters. — Bill larger and stronger ; female darker, more chest- 

 nut-brown. 



Measurements. — Males (10 from Bocas del Toro, Veraguas, and 

 Costa Rica), wing 76.9-81.2 (79.4), tail 70.8-79.1 (74.2), culmen 

 from base 22.1-24.2 (22.8), tarsus 32.5-35.1 (33.7, average of 9) mm. 



Females (10 from Veraguas and Costa Rica), wing 74.5-79.3 

 (76.4), tail 68.0-78.8 (73.3), culmen from base 21.3-23.5 (22.3), 

 tarsus 32.2-34.8 (33.8) mm. 



Resident. Rare, in heavy forest, apparently in the upper Tropical 

 and lower Subtropical zones in Chiriqui, western Bocas del Toro, and 

 western Veraguas. 



